Schwab Advisor Services is signing up advisor assets at a pace that tracks its historical average, Executive Vice President of Advisor Services Bernie Clark said.

Charles Schwab’s unit for serving registered investment advisors had net new assets of $12.6 billion for the first quarter, the nation’s largest discount broker reported today. If extrapolated over four quarters, that number tracks the company’s average net new assets of about $50 billion last year, Clark said.

Even the number of new brokers who joined Advisor Services roughly tracks last year’s performance. Clark said 41 firms signed up with Schwab last quarter, about a fourth of the 166 teams that joined Schwab in total for 2011.

While in the past the breakaways have been predominately from the wirehouses, he said, about a third now are from independent broker/dealers. Clark said some of those IBD breakaways had originally fled from wirehouses.

“Now they’re finding full independence is more in their interest and their clients’ interest, so they’re going the full way,” he said.

About 80 percent of the net new asset growth at Schwab Advisor Services comes from new assets brought on by existing advisors, while the rest are advisors who have just joined the unit, he added. Net new assets at the unit were up 37 percent from the fourth quarter of 2011 but down 11 percent year over year.

Clark said he thinks the year-over-year decline in net new assets resulted from stronger onboarding of investor money seen in early 2011, a momentum that halted with the volatile markets of the following summer. Total net new assets at Schwab, including those from retail investors, reached $38.9 billion last quarter.

Advisors representing about $30 billion in assets are discussing the possibility of joining the custodian, Clark said. Last year the company signed up breakaway advisors with $12 billion in assets, down slightly from $12.6 billion in 2010.

“It’s just really consistent,” Clark said. “There are always people talking to us.”

Schwab reported a record $735.9 billion in assets at Advisor Services at the end of last quarter, up 7 percent year over year and 8 percent sequentially. Schwab had total client assets of $1.83 trillion at the end of the last quarter.

The company had net income of $195 million on net revenues of $1.19 billion last quarter. A year earlier it had net income of $243 million on net revenue of $1.21 billion.

Meanwhile, the new franchise program the company announced more than a year ago is proceeding slowly. Schwab said just two advisors have opened franchise branches, in Nashua, N.H. and Mequon, Wis. so far.

It’s had 2,000 inquiries from interested advisors and is being “very deliberate” about who it chooses to run its franchises, a company spokeswoman said.